Adolescents with co-occurring mental health and substance use disorders typically must seek treatment from two separate service systems. Research suggests that mental health and substance use treatment provided in separate or parallel systems are fragmented and ineffective for persons with co-occurring disorders. Growing empirical evidence suggests the effectiveness of integrated mental health and substance use treatment on health outcomes in adult populations, however no information is available on the availability, utilization or benefits of integrated services for adolescents in rural delivery systems. The objective of this research is to examine whether specific clinical and non-clinical characteristics can distinguish adolescents with co-occurring disorders most likely to achieve positive clinical outcomes from those not able to benefit meaningfully across integrated and nonintegrated treatment settings. It is hypothesized that non-clinical factors will predict the receipt of both mental health and substance use treatment among adolescents with co-occurring disorders. It is also hypothesized that adolescents that need and receive both services will have a greater degree of improvement than adolescents with co-occurring disorders treated for only their mental health or substance use needs. Results will have significant impact on state and local planning and reform efforts for the development of integrative services for adolescents in rural communities. The clinical and psychosocial characteristics of 300 randomly selected adolescents will be assessed at admission to and discharge from programs licensed to provide mental health and substance use treatment, mental health treatment only and substance use treatment only. This research has the following aims: 1) examine whether adolescents with co-occurring mental health and substance use needs receive treatment for both needs, 2) assess whether non-clinical factors predict the receipt of both mental health and substance use treatment for adolescents with co-occurring disorders, and 3) assess whether adolescents with co-occurring disorders who need and receive both mental health and substance use treatment experience a greater degree of improvement as compared to adolescents with co-occurring disorders who receive a single treatment.